Pattern substrate and touch panel using the same

ABSTRACT

A touchscreen display device includes a display module and an electrically conductive and light transmissive layer provided over the display module to allow detection of touch input. The electrically conductive and light transmissive layer includes a transparent substrate and a transparent layer provided over the transparent substrate. The transparent layer has first and second surfaces, which are opposing surfaces, and the first surface faces the transparent substrate. The second surface includes a plurality of protrusions extending in different directions such that the plurality of first protrusions intersect to form recess regions on the second surface. The recess regions include a plurality of second protrusions, and the second protrusions have a height and a width less than the first protrusions. At least one metallic wiring layer is formed on the plurality of first protrusions including at locations where the first protrusions intersect.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation-In-Part application of U.S.application Ser. No. 14/358,701 having a 371(c) filing date of May 15,2014, which is a U.S. National Stage application of InternationalApplication No. PCT/KR2012/010739 filed Dec. 11, 2012, claiming priorityto Korean Application No. 10-2011-0137217 filed on Dec. 19, 2011, whoseentire disclosures are incorporated herein by reference.

BACKGROUND

1. Field

The present disclosure relates to a transparent substrate having a nanopattern for use to a touchscreen of a display module.

2. Related Art

When manufacturing a semiconductor device, a word line, it isnecessarily required to implement various fine patterns such as a digitline, a contact and the like. A lithograph technology has been generallyapplied to form these fine patterns.

A contact lithograph method which has been traditionally and widely usedenables the pattern to be formed throughout a wide area. However, due toa limit of the diffraction of light, it was problematic that a pitch ofthe fine pattern which can be formed is limited (1˜2 μm).

Accordingly, to solve this problem, a stepper method, a scanner method,a holographic lithography method and the like were developed. However,these methods need complicated and sophisticated equipment and incurhigh expenses. Further, the methods have a limit in view of the factthat an area which can form a pattern is limited. That is, theconventional lithograph method is basically limited to implementnonoscale fine patterns due to the problems such as a limitation ofequipment or a process property. More specifically, upon the use of theconventional lithography technology, it would be difficult to implementnanoscale patterns which are uniformly formed throughout a large area ofmore than 8 inch.

According to the aforesaid problems, a method of forming a porous metalthin film using a porous template made of a metal material as disclosedin Korean Laid-Open Patent Publication No. 2011-0024892, and formingnano patterns using the porous metal thin film as a catalyst wassuggested. The method was problematic in that because the poroustemplate should be prepared in advance, it is inconvenient to use themethod, and because a catalyst growth method is used, nano patterns canbe formed at only desired regions. Moreover, it was problematic that thenano patterns cannot be formed on a transparent substrate.

The above references are incorporated by reference herein whereappropriate for appropriate teachings of additional or alternativedetails, features and/or technical background.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to thefollowing drawings in which like reference numerals refer to likeelements, wherein:

FIG. 1 and FIG. 2 are flow charts showing the order of a method ofmanufacturing a transparent substrate having a nano pattern according tothe present disclosure.

FIG. 3 through FIG. 9 are the exemplary views of processes illustratingroughly the manufacturing processes of a transparent substrate having anano pattern according to the present disclosure.

FIG. 10 illustrates a touchscreen comprising the transparent substratehaving a nano pattern of the present disclosure.

FIGS. 11A-11C illustrate the arrangement of the transparent substrate asa touch screen in various display module configurations.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 and FIG. 2 are flow charts showing the order of a method ofmanufacturing a transparent substrate having a nano pattern according tothe present disclosure. A method of manufacturing a transparentsubstrate having a nano pattern according to the present disclosure mayinclude: forming a resin layer made of a transparent material on atransparent substrate (S1); forming at least one or more unit patternparts, which are composed of a first and a second pattern areas in whicha plurality of grid patterns are formed, and a protrusion pattern formedbetween the first pattern area and the second pattern area, on the resinlayer (S3); and forming a nanoscale metal layer on the protrusionpattern (S5).

A material of the transparent substrate in used in step S1 may be glass,quartz, a polymer made of a transparent material, for example, publiclyknown polymer materials such as PET (polyethylene terephthalate), PC(polycarbonate), PI (polyimide). In addition to this, various flexiblesubstrates may be used. The material is not limited.

After the transparent substrate is prepared, a resin layer is formed byapplying a resin made of a transparent material to the transparentsubstrate. At this time, the resin may use a thermosetting polymer or aphoto curable polymer. Meanwhile, to improve a bonding ability betweenthe resin layer and the transparent substrate, the resin layer may bealso formed by coating the transparent substrate with an adhesive beforeapplying the resin, and thereafter applying the resin to the transparentsubstrate.

After step S1, at least one or more unit pattern parts, which arecomposed of a first pattern area and a second pattern area in which aplurality of grid patterns are formed, respectively, and a protrusionpattern formed between the first pattern area and the second patternarea, is formed on the resin layer (S3). Specially, step S3 may beperformed as described below.

First, a master mold is produced (S31), the master mold having at leastone or more unit mold pattern parts, which are composed of the firstmold pattern area and the second mold pattern area in which a pluralityof grid mold patterns are formed respectively, between the plurality ofgrid mold patterns there are formed with recesses, and a concave moldpattern formed between the first mold pattern area and the second moldpattern area.

The plurality of nanoscale grid mold patterns are first formed on anoriginal material of the master mold using a space lithography process,for example, “a method of manufacturing a nanoscale pattern having alarge area” as described in Korean patent application No.10-2010-0129255. The master mold of the present disclosure may beproduced by forming a concave mold pattern to divide a first moldpattern area and a second mold pattern area and forming one or more unitmold pattern parts. At this time, specifically, the formation method ofthe concave mold pattern may be performed by an electron-beamlithography process. However, the present disclosure is not limited tothis.

Meanwhile, a width (A) of a recess between the gird mold patterns of thefirst mold pattern area or the second mold pattern area may be formed ina range of 50 to 100 nm. A width (B) of concave or squared recess moldpattern may be formed in a range of 200 to 1000 nm. The width (C) of theprotrusions in the first mold pattern area or the second mold patternarea may be in a range of 50 to 100 nm. The master mold produced by thismethod is reusable until it is damaged. Furthermore, the master mold cancontinue to use at an imprinting process, causing economical advantagessuch as the reduction of a raw material charge and a production cost.

Then, the master mold produced in step S31 is arranged in an upper partof the resin layer, and one or more unit pattern parts corresponding toone or more unit mold pattern parts are formed on the resin layerthrough an imprinting process for pressurizing the resin layer (S33).Here, the unit pattern parts mean a structure including the firstpattern area corresponding to the first mold pattern area, the secondpattern area corresponding to the second mold pattern area, and theprotrusion pattern unit corresponding to the concave mold pattern. Theplurality of grid patterns corresponding to recesses between theplurality of grid mold patterns are provided in the first pattern areaand the second pattern.

A process of hardening the resin layer is performed (S35). At this time,in a case where the resin layer is made of a thermosetting polymer, theresin layer is hardened by applying heat thereto. In a case where theresin layer is a photo curable polymer, the resin layer is hardened byirradiating ultraviolet rays thereto. Thereafter, step S3 of the presentdisclosure may be conducted by releasing the master mold from the resinlayer (S37).

Then, in step S5, the nanoscale metal layer is formed on the protrusionpattern of the resin layer. A metallic layer is first deposited on thegrid patterns and the protrusion pattern. At this time, the depositedmetal may use any one of Al, Cr, Ag, Cu, Ni, Co and Mo or an alloythereof. However, the present disclosure should not be limited to this,and other metals may be appropriately used as need. The depositionmethod of the metal may be at least one method of a sputtering method, achemical vapor deposition method, and an evaporation method. However,this is only one example. In addition to the methods, all depositionmethods, which have been developed and commercialized or can be embodiedaccording to future technical development, may be used.

Meanwhile, a height of depositing the metal may be formed to be morethan a pitch value (See “P” of FIG. 7) of the grid patterns, and themetal may be uniformly deposited on each grid pattern and the protrusionpattern. The pitch value being a distance between a center of aprotrusion to a center of an adjacent protrusion. This pitch value maybe in a range of 100 to 200 nm. This is intended to easily remove themetal formed on the grid patterns at an etching process later.

After the metal is deposited, a wet etching process is performedthereon, so isotropic etching is performed at exposed three sides of themetal. Thus, the metal deposited on the grid patterns is etched, or apart bonded to the grid patterns is peeled off. Consequently, the metaldeposited on the grid patterns is removed, and the metal on theprotrusion pattern remain so as to form the metal layer. The reason whythe metal deposited on the grid patterns is removed and the metal on theprotrusion pattern remains so as to form the metal layer is because acontact area between the metal deposited on the grid patterns and anetching solution used during the wet etching process is more than themetal deposited on the protrusion pattern. Thus, the transparentsubstrate having the nano pattern of the present disclosure, includingthe nano pattern and nanoscale metal layer may be produced.

As the wet etching process is used, the process can be performed even atroom temperature, and as the manufacturing process of the master moldcan be performed separately, flexible processes can be secured.Furthermore, the master mold is available until it is damaged, causingthe reduction of a raw material charge and a production cost.

The nano patterns may be uniformly implemented throughout the wide areaof the transparent substrate, and the nanoscale metal layer may be alsouniformly formed on the transparent substrate. Thus, it is advantageousthat the transparent substrate having electrical conductivity equal toITO can be provided at a low cost, and an Ag mesh which is emerging as asubstitute for the ITO can be produced as a nanoscale pattern.Accordingly, the transparent substrate with nano patterns can beutilized in various fields such as a touch panel, a liquid crystaldevice, a solar cell and the like.

FIG. 3 through FIG. 9 are the exemplary views of processes illustratingroughly the manufacturing processes of a transparent substrate having anano pattern according to the present disclosure. As illustrated in FIG.3, a structure 10 a in which the plurality of nanoscale grid moldpatterns 11 on an upper surface thereof are formed is produced. At thistime, the space lithograph process may be used as a method of formingthe grid mold pattern 11. This is the same as described in theexplanation of FIG. 2.

Thereafter, as illustrated in FIG. 4 and FIG. 5, a master mold 10 havingat least one or more unit mold pattern parts 10 b are produced bypatterning the structure 10 a as illustrated in FIG. 3 through anelectron-beam lithography process. At this time, the unit mold patternparts 10 b are composed of a first mold pattern area 13, a second moldpattern area 17, and a concave or squared recessed mold pattern 15formed between the first mold pattern area 13 and the second moldpattern area 17. The mold pattern area 13 and the second mold patternarea 17 have a plurality of grid mold patterns 11 with recesses betweenthem. The grid mold pattern 11 is shown as a series of protrusions,e.g., squared protrusions, but other shaped protrusion patterns arepossible.

Here, a width (B) of the concave mold pattern 15 is formed to be widerthan a width (A) of the recess between the patterns of the first moldpattern area 13 or a width of the recess between the patterns of thesecond mold pattern area 17. More specifically, the width (B) of theconcave mold pattern 15 may be formed in the range of 200 to 1000 nm.The width (A) of the recess between the patterns of the first moldpattern area 13 or the width (A) of the recess between the patterns ofthe second mold pattern area 17 may be formed in the range of 50 to 100nm. The width (C) of the protrusions may be in the range of 50 to 100nm. However, the present disclosure is not limited to this. Also, adepressed depth of the concave mold pattern 15 may be formed to bedeeper than a height of the grid mold pattern 11. In an embodiment, theheight of the pattern 15 is greater than the height of the pattern 11and the height of the pattern 11 is less than the height of the pattern15.

Then, as illustrated in FIG. 6, the imprinting process for pressurizingthe resin layer 30 formed on the transparent substrate 20 using themaster mold (10 of FIG. 5), in which one or more unit mold pattern parts10 b are formed, is conducted. The detailed explanation on thetransparent substrate 20 and the resin layer 30 is the same as describedin the explanation of FIG. 1 and FIG. 2, and thus is omitted. The mastermold (10 of FIG. 5) is released from the resin layer 30 after applying aphoto curing process or a heat curing process, as illustrated in FIG. 7,so that one or more unit pattern parts 30 b corresponding to the unitmold pattern parts (10 b of FIG. 5 and FIG. 6) may be formed on theresin layer 30. Here, the unit pattern parts 30 b are composed of thefirst pattern area 33, the second pattern area 37, and the protrusionpattern 35 formed between the first pattern area 33 and the secondpattern area 37. The first pattern area 33, and the second pattern area37 have the plurality of grid patterns 31, and the protrusion 35 haveshapes and patterns that complements the shapes and patterns recesses ofthe first mold pattern area 13, of the second mold pattern area 17, andthe recess 15.

Due to the imprint of the master mold on the resin layer 30, thedimensions are substantially the same in a complementary manner. A width(E) of the protrusion pattern 35 may be formed to be wider than a widthof the grid pattern of the first pattern area 33 or a width of the gridpattern of the second pattern area 37. More specifically, the width (E)of the protrusion pattern 35 may be formed in a range of 200 to 1000 nm,i.e., width (E) equals width (B). The width (D) of the grid pattern 31of the first pattern area 33 or the width of the grid pattern of thesecond pattern area 37 may be formed in a range of 50 to 100 nm, i.e.,width (D) equals width (A). The width (F) of the recesses of the firstpattern area 33 or the second grid pattern area 37 may be formed in arange of 50 to 100 nm, i.e, width (F) equals width (C). However, thepresent disclosure is not limited to this. Also, a height of theprotrusion pattern 35 is formed to be higher than a height of the gridpatterns 31.

Then, the metal is deposited on the grid patterns 31 and the protrusionpattern 35, and the metal deposited on the grid patterns 31 is removedthrough the wet etching process, so that the nanoscale metal layer 40may be formed on the protrusion pattern 35, as illustrated in FIG. 8.The width of the metal may be the same or smaller than the width (E),and the height of the metal layer 40 may be greater than or equal to 100nm. In the above disclosed embodiments, although the protrusion pattern35 is illustrated as higher than grid patterns 31 formed in the firstpattern area and the second pattern area, the present disclosure is notlimited thereto. The protrusion pattern 35 may also be substituted witha wide pattern 35 that is equal in height to the grid patterns 31 (i.e.,narrow patterns 31), but is wider than individual narrow patterns 31.

Thus, the transparent substrate having the nano pattern with a largearea as illustrated in FIG. 9 can be obtained, which illustrates a topview of transparent substrate, where FIG. 8 is a section view of thearea shown in dotted lines. As shown, the metal layer 40 are formed in Xand Y directions on top of the protrusion pattern 35 to form a mesh of xand y signal lines x1-x4 and y1-y4 with a plurality of first and secondpattern areas 33 and 37.

FIG. 10 illustrates a touchscreen 50 incorporating the transparentsubstrate having nano pattern, which is provided in area A. A black mask51 is provided at the periphery of The touchscreen display device 50 tohide any circuitry or visible signal lines, e.g., x and y signal linesof the transparent substrate, which are connected to input and/or outputlines 52.

FIG. 11A illustrates a first implementation of the touchscreen 50 in adisplay device 60. In this embodiment, the touchscreen 50 using atransparent film 32 with signal lines, e.g., x or y signal lines, isadhered using an adhesive 62 between an LCD module 64 and a window 66.

FIG. 11B illustrates a second implementation of the touchscreen 50 in adisplay device 60. In this embodiment, the touchscreen 50 using glass 34as the transparent substrate with signal lines, e.g., x or y signallines, is adhered using an adhesive 62 between an LCD module 64 and awindow 66.

FIG. 11C illustrates a third implementation of the touchscreen 50 in adisplay device 60. In this embodiment, a window 66 having either a filmor glass as a substrate with x or y signal lines serve as thetouchscreen 50. The touchscreen 50 is adhered to the LCD module 64 usingan adhesive 62.

According to the present disclosure, it is advantageous that thenanoscale grid patterns can be uniformly formed throughout a wide areaof the transparent substrate.

Also, according to the present disclosure, it is advantageous that thenanoscale metal layer as well as the aforesaid grid patterns can be alsouniformly formed on the transparent substrate, thereby enabling thetransparent substrate having electrical conductivity equal to ITO to beprovided at a low cost.

In addition, the master mold used in the present disclosure isrecyclable until it is damaged, causing economical advantages such asthe reduction of a raw material charge and a production cost.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A touchscreen display device comprising: adisplay module; and an electrically conductive and light transmissivelayer provided over the display module and allowing detection of touchinput, the electrically conductive and light transmissive layer having atransparent substrate; a transparent layer provided over the transparentsubstrate, the transparent layer having first and second surfaces, whichare opposing surfaces, the first surface facing the transparentsubstrate, the second surface having a plurality of protrusionsextending in different directions such that the plurality of firstprotrusions intersect to form recess regions on the second surface, andthe recess regions having a plurality of second protrusions, the secondprotrusions having a height and a width less than the first protrusions;and at least one metallic wiring layer formed on the plurality of firstprotrusions including at locations where the first protrusionsintersect.
 2. The touchscreen display device of claim 1, wherein thedisplay module is a liquid crystal display module.
 3. The touchscreendisplay device of claim 1, wherein the transparent substrate has firstand second surfaces, the first surface of the transparent substratefacing the display module, and the second surface facing the secondsurface of the transparent layer.
 4. The touchscreen display device ofclaim 1, wherein the second surface of the transparent layer face thedisplay module.
 5. The touchscreen display device of claim 1, whereineach of the first protrusions has a width of 200-1000 nm, and each ofthe second protrusions has a width of 50-100 nm.
 6. The touchscreendisplay device of claim 1, wherein the at least one metallic wiringlayer has a thickness greater than a pitch value between two adjacentsecond protrusions.
 7. The touchscreen display device of claim 1,wherein the transparent layer is made of resin material.
 8. Thetouchscreen display device of claim 7, wherein the resin material is oneof a thermosetting polymer or a photo-curable polymer, the polymer beingone of PET, PC and PI.
 9. The touchscreen display device of claim 1,wherein the substrate is at least one of glass or quarts.
 10. Thetouchscreen display device of claim 1, wherein the plurality of firstprotrusions form a mesh layout on the second surface of the resin layer.11. The touchscreen display device of claim 1, wherein the plurality offirst protrusions comprises a first group of protrusions extending in afirst direction and a second group of protrusions extending in a seconddirection, the first and second directions being different directions.12. The touchscreen display device of claim 11, wherein the first andsecond directions are perpendicular to each other such that the recessregions have a rectangular shape.
 13. The touchscreen display device ofclaim 1, wherein a recess is proved between adjacent second protrusionsto form a pattern of protrusions and recesses.
 14. The touchscreendisplay device of claim 1, wherein the plurality of first protrusionscomprises a first group of protrusions extending in a first directionand a second group of protrusions extending in a second direction, thefirst and second directions being different directions, the plurality ofsecond protrusions extending in the first direction of the first groupof protrusions.
 15. The touchscreen display device of claim 1, whereinthe at least one metallic wiring layer comprises at least one of Al, Cr,Ag, Cu, Ni, Co or Mo.
 16. The touchscreen display device of claim 1,wherein an electrical conductivity of the electrically conductive andlight transmissive layer is equal to indium tin oxide (ITO).
 17. Thetouchscreen display device of claim 1, wherein a width of a firstprotrusion is 200-1000 nm.
 18. The touchscreen display device of claim1, wherein each of the plurality of first protrusions has a width widerthan a width of each of the plurality of second protrusions.
 19. Thetouchscreen display device of claim 1, wherein each of the first andsecond protrusions have a rectangular shape.